View instructions
The air brakes endorsement applies to applicants who wish to drive a vehicle with air brakes in Class A, B, or C CDL. To drive a vehicle with air brakes, you must pass the air brake component of the Texas CDL knowledge test. The TX CDL air brakes test consists of 25 questions, and you'll need at least 20 correct answers to pass (80%). The test covers the information found in the air brakes section of the Texas CDL Manual. Take this TX CDL practice test now to prepare for the actual air brakes test!
1. Stepping on and off the brake pedal several times:
may cause air leaks.
reduces the air pressure in the tanks.
may result in dangerously thin linings.
All of the above.
2. Older trailers do not have spring brakes. If the air supply leaks away:
the ABS won't work properly.
the trailer will stop normally.
there will be no emergency brakes.
All of the above.
3. Before driving a vehicle with a dual air system, the air compressor should build up a minimum of _____ pressure in both the primary and secondary systems.
75 psi
10 psi
50 psi
100 psi
4. Trailers built on or after March 1, 1998 are required to be equipped with anti-lock brakes. These trailers will have:
yellow malfunction lamps on the left side.
red malfunction lamps on the left side.
blue malfunction lamps on the right side.
yellow malfunction lamps on the right side.
5. Pressing and releasing the brake pedal unnecessarily can:
causes friction, which slows the vehicle.
apply more air pressure.
let air out faster than the compressor can replace it.
causes all the air to be lost.
6. If the ABS is not working:
the vehicle will have weak brakes.
you still have normal brake functions.
the vehicle will have no brakes.
None of the above.
7. Antilock brakes:
help you stop faster.
let you drive faster.
decrease your stopping distance.
None of the above.
8. You are driving a vehicle with air brakes when the low air pressure warning light and buzzer come on. You should:
pull off the road and stop immediately.
slow down and test your brakes.
apply the brakes as hard as you can.
activate your hazard lights and drive to the nearest place where you can stop.
9. When you apply the brakes, the brake shoes and linings are pushed against:
the S-cam.
the supply pressure gauge.
the safety relief valve.
None of the above.
10. The parking brake:
should be used whenever you park.
should be used when you need to apply the brakes firmly.
should be used when driving in bad weather.
All of the above.
Page 1 of 3
Next page

TX Air Brakes Test

Number of questions: 25
Correct answers to pass:20
Passing score:80%
Share This Online CDL Test
Rate this Air Brakes Test
5 out of 5
based on 233 votes